The present invention relates to transport of wheeled vehicles, and in particular concerns carrying racks and their use for supporting motor vehicles, to efficiently utilize a limited amount of available space, such as the space available within an intermodal cargo container.
Use of standard intermodal cargo containers has become the preferred way to transport pilferable or easily damaged cargo over long distances, particularly where the transport involves carriage both by sea and over land. It is also known to place automobiles on racks which are carried inside cargo containers.
Because the width of automobiles is only slightly less than the width of the available space within a container it is very difficult for a person to maneuver automobiles under their own power within a container to effect loading and unloading, and there is a risk of damaging an automobile while entering or leaving the vehicle within a container. Accordingly, various racks have been devised to carry automobiles into and out from containers and to support them securely immobilized one above another within a container, in order to efficiently utilize the space available within a container.
One previously known arrangement is described, for example, in Preller et al. U.S. Pat. No. 5,213,458, which discloses an apparatus for supporting automobiles in two tiers within containers. The apparatus includes a dunnage device for keeping the system properly stabilized longitudinally within a container, but insertion of such apparatus into a container is more difficult than is desirable, since the supporting apparatus has to be skidded into place in a cargo container. Automobiles have to be driven up an incline to the position for transport, and the apparatus requires a forklift to raise an upper tier portion into place.
Gearin et al. U.S. Pat. No. 4,768,916 discloses an automobile carriage rack which requires automobiles to be placed in the rack prior to insertion of the rack into a container. The apparatus requires the use of lifting devices such as gantry cranes to raise automobiles into desired positions while the carriage rack remains outside the cargo container, and to lower the automobiles for removal at the destination. Because the loaded rack must be inserted through the doorway provided in an end of a container, space in the container above the height of the top of the doorway of the container remains unused.
Kato et al. U.S. Pat. No. 4,917,557 discloses a two-tier rack equipped with a pair of wheels at one end, to carry one end of the rack while it is moved by raising the other end. The rack must be loaded with automobiles prior to insertion into a cargo container, and the upper storage tier support portion of the rack is raised to an inclined position by merely pivoting it about an axis located low at one end of the device. A significant amount of space within a container may be wasted, because vehicles carried on the rack are not directly above one another, requiring the rack to therefore be significantly longer than the longest vehicle which can be carried upon it. Also, because one end of the rack must be raised to maneuver the rack into a container, available interior space above a height somewhat lower than the container doorway is not useable because of the clearance needed.
Dluhy U.S. Pat. No. 3,675,795 discloses a tiltable rack for supporting an individual automobile. A pair of legs hold one end of the rack in a raised position within a container so that several automobiles on such racks may be carried within a container with one overlapping another longitudinally. The device requires use of a lift device, however, to carry one end of the rack as it is moved into the container, and dunnage is required behind the support legs of the last such rack placed into the container.
Spier et al., U.K. patent application GB 2050304 discloses an automobile-supporting apparatus which is placed within a cargo container empty. After a first automobile is placed on the device, one end of the automobile is raised by lifting a pair of arms which pivot about an axis located at the other end of the device. However, when the movable arms are in their lowered position, the rack is taller than desired, thus occupying an unnecessarily large volume during return shipment of the empty rack. Also, the height of the device requires a vehicle's wheels to be replaced by special rings to obtain vertical clearance for placement of the automobiles. This adds cost and labor which it is desirable to avoid.
Smith U.S. Pat. No. 4,455,119 discloses a specially-equipped automobile-carrying trailer including wheel-guiding tracks along which transversely-oriented bars are adjustably movable longitudinally of the tracks to provide a longitudinal space between a pair of the bars. The device receives a tire between the bars and thus holds the vehicle in place longitudinally along the channels. The automobiles must be driven into the trailer, however, and so there is the risk of damage to the automobiles.
McCormick U.S. Pat. No. 2,617,368 discloses an automobile-carrying railroad car incorporating rack-and-pinon apparatus for independently raising the opposite ends of a rack supporting a first automobile, to provide space beneath the raised automobile for a second automobile. The lift apparatus, however, is apparently not easily removable from a railroad car in which it is installed, and would therefore interfere with use of the same car for other types of cargo.
A special automobile-carrying rack disclosed by J. B. Hunt Company apparently must be placed in position within a container while empty and utilizes a separate cradle to support both tires on a respective end of an automobile. Each cradle is supported by a hanger assembly at each side of the rack, and each hangar assembly is attached to a post including a mechanical lift device to raise the hangers. A coordinated drive arrangement provides for raising the hangers and cradle supporting one end of the automobile twice as far as those at the other end of the automobile, providing space for a second automobile to be driven into place beneath the first. The automobiles must be steered into the rack on their own wheels, however, and it is difficult to exit from the automobiles once they are in position. An adjustable portion of the frame may be extended to prevent a subsequent frame from approaching a first frame too closely.
It is known to place vehicles onto the deck of a flatbed truck for transport by tilting the deck rearward, and then translating the deck rearward and downward in the direction of its slope, until its rear end reaches the ground. Thereafter a vehicle is moved up the inclined deck and fastened to the deck. The deck is then translated forward and upward along the direction of its slope, and finally the deck is tilted forward to resume a level orientation. Such a procedure, however, is undesirably complex and hazardous for raising a vehicle into a position for carriage within a container.
Prior art apparatus and methods for supporting automobiles within intermodal cargo containers, then, have presented difficulties in use, have left available space unusable within containers, have required unnecessarily large volumes for return transport of empty apparatus, and often require special equipment for loading and unloading.
What is needed, then, is an improved apparatus for supporting wheeled vehicles, and a method for use of such apparatus, which enables a maximum number of wheeled vehicles to be transported within an intermodal cargo container, which permits the entire internal height of a cargo container to be used without limitation by the height of the doorway at an end of such a container, which allows vehicles to be loaded into or unloaded from the container easily without special facilities, and which is itself easily inserted into a container, yet which rests securely on the floor of the container once located within the container. Such a vehicle-supporting apparatus should also be collapsible to occupy a minimum amount of space, so that container volume is not wasted in return shipment of empty apparatus, and so that a large proportion of containers used to ship vehicles in one direction can be used for shipment of other cargo in the opposite direction.